System and method for projecting storms using NEXRAD attributes

ABSTRACT

The subject invention provides an improved system and method for combining data obtained from the NEXRAD™ system of the National Weather Service (“NWS”) with geographical and topological database information to achieve an improved and informative graphical storm-tracking display able to project the movement of a storm with a single user-operation. The method of projecting storm movement includes the following steps: collecting NEXRAD data attributes from a weather data source; calculating storm position using the collected NEXRAD attributes; calculating projected storm movement using the storm position and the collected NEXRAD attributes; displaying a graphic representation of the projected storm movement.

Cross Reference to Related Application

This application is a continuation of U.S. application Ser. No.09/021,448, filed Feb. 10, 1998, now U.S. Pat. No. 6,125,328 whichclaims the benefit of Provisional Application Ser. No. 60/036,952, filedFeb. 10, 1997, both of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an improved system and method forcombining data obtained from the NEXRAD™ system of the National WeatherService (“NWS”) with geographical and topological data base informationto achieve an improved and informative graphical storm-tracking displayable to predict and project the direction of a storm with a singleuser-operation.

2. Technical Background

NEXRAD is a system of weather services provided by the NWS. NEXRADemploys a system of radars scattered throughout the country whichprovides weather data to subscribers. Subscribers, such as televisionstations desiring to transmit weather broadcasts, use data from theNEXRAD system in its basic form. Current systems of subscriberstypically extract simple storm information from the NEXRAD data toprovide viewers with basic storm location information.

One NEXRAD service is the “NEXRAD Attributes.” This service provides thesubscribers with detailed information concerning storms detected at eachNEXRAD radar site. The NEXRAD Attributes data includes the followinginformation for each storm:

ID a unique 3-digit identifier AZ the direction of the storm in degreesfrom the radar source RANGE the distance of the storm in nautical milesfrom the radar source TVS the likelihood of a tornado vortex signature(Yes or No) MESO the likelihood of mesocyclonic activity (Yes or No)HAIL the likelihood of hail (% change of hail, % chance of severe hail,approximate hail size in inches) DBZM the maximum DBZ level (ameasurement of precipitation intensity) FCST_ANGLE forecasted movementangle (storm path) in degrees FCST_MVMT forecasted movement speed innautical miles per hour

The typical current NEXRAD system used by a NEXRAD subscriber receivesNEXRAD data via a satellite downlink or over a wired network connectioninto a computer, such as the computer illustrated in the attached FIG.1. Then, the current subscriber's system extracts the azimuth and rangeinformation of the subject storm. From this information, the currentsystems can plot a two dimensional representation of the storm. Most ofthe other information in the NEXRAD Attributes goes unused by currentsystems, although the user, typically a meteorologist, can review thisdata manually.

One problem with a subscriber's current system is that in order topredict the movement of a storm, the user must manually createprojections from the NEXRAD Attributes data. Current systems do not havethe capability to create a graphical representation of the stormmovement from the NEXRAD Attributes data without substantial humaninvolvement.

Moreover, the current graphical storm display is typically limited tosimple two dimensional representations of the storm's location andlittle else. Typically the viewers of weather displays based on thecurrent systems have only a vague concept of the proximity of the stormto their location. Current systems are incapable of displaying NEXRADprojection information concerning those storms in any appreciablegraphical way.

SUMMARY OF THE INVENTION

A method for projecting storms using NEXRAD attributes comprising thesteps of: (a) collecting NEXRAD data attributes from a weather datasource; (b) calculating storm position using the collected NEXRADattributes; (c) calculating projected storm movement using the stormposition and the collected NEXRAD data attributes; (d) displaying agraphic representation of the projected storm movement; (e) determiningthe communities in the path of the projected storm movement.

In addition, the present invention, in a preferred embodiment furthercomprises the following steps: (f) displaying the communities indicatingthe estimated time of arrival for the projected storm; (g) sortingmultiple storms; (h) displaying the sorted storms in order of priority;and (i) displaying single storm details.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of the preferred embodiment of the internal devicesof a computer for use in the present invention.

FIG. 2 is a diagram of the computer of FIG. 1 and its use of the NEXRADradar's latitude/longitude and the storm's distance and direction fromthe NEXRAD radar to determine the storm's exact latitude and longitude.

FIG. 3 is a diagram of the computer of FIG. 1 and its use of theinformation from the NEXRAD attributes and database information tocreate storm projections of the present invention.

FIG. 4 is a diagram generally describing the storm tracking algorithm ofthe present invention.

FIG. 5 is representative of a graphical output of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention improves over the prior art by utilizing theNEXRAD Attributes storm projection information, represented by thevariables FCST_ANGLE and FCST_MVMT above and shown in FIG. 3, to providethe users of the present invention the ability to graphically displaystorm projection information with a single operation. The presentinvention extracts the NEXRAD Attributes storm projection informationand adapts that information for graphical display. The use of theprojection data in the present invention allows the user to have thestorm location information graphically displayed, such as on a computermonitor screen or television set, overlaid with a graphicalrepresentation of the projected movement of the storm.

The steps which the present invention utilizes to achieve a stormprojection system that will provide the user with storm predictioninformation in one operation can be briefly summarized as follows:

The first step is collecting NEXRAD Attributes for use by the stormprojection system by receiving NEXRAD Attributes information via asatellite downlink, wired network, or other information transfer medium,and storing this information in a database.

In a preferred embodiment, the database contains the followingattributes for each storm:

Attribute Range of Values The presence of a Tornadic Vortex SignatureYES or NO (TVS) The presence of Mesocyclonic activity (MESO) YES or NOChance of Hail 0% to 100% Chance of Severe Hail 0% to 100% Hail Size ininches 0.00″ to 4.00+″ Maximum Storm DBZ (measurement of rainfall 30 to75+ DBZ intensity) Height of max DBZ reading in the Storm 1-75 thousandof feet Storm Height 1-75 thousand of feet Storm position (latitude andlongitude) N/A Storm forecasted angle 0 to 359 degrees Storm forecastedmovement 0 to 60+ mph Storm Vertically Integrated Liquid (VIL) 0 to 75+kg/m³ Range in nautical miles from radar Azimuth (direction) in degreesfrom radar

The database information is accessed to report the contents andcharacteristics of storms and to track the storms in near real-time.

Second, in response to a user request for a projection of a storm'smovement, the system retrieves the NEXRAD Attributes information for asubject storm stored in the first step above. The user request may bemade using a manual input device such as a mouse or keyboard as shown inFIG. 1.

Third, the system calculates a storm projection arc to create agraphical representation of the storm for display, said calculationcomprising the steps of:

(a) Using the storm's offset in meters from the view center of thegraphical display (FIG. 2) to find the storm's position inlatitude/longitude;

(b) Using the storm information (including fanout in degrees, directionin degrees, projection length in meters, and position as an offset inmeters) to find the four corners of an arc describing the storm'sprojected path (the “storm projection arc”);

(c) Using the storm information (including fanout in degrees, directionin degrees, projection length in meters, and position as an offset inmeters) to find the storm's projected position after moving “length”meters;

(d) Using the storm information (including fanout in degrees, directionin degrees, projection length in meters, and position as an offset inmeters) to find the center of a bounding circle that helps define thelimits of the projection;

(e) Using the four corners of the storm projection arc to define themaximum latitude, maximum longitude, minimum latitude, and minimumlongitude at which a place in this track may be positioned;

(f) Using the four corners of the storm projection arc (see (b) above)to define the bounding lines of the arc that will define the stormprojection;

Fourth, a general database of geographical information (FIG. 3) isstored on the computer in the form of a database containing latitude andlongitude information, as well as other identifying and prioritizinginformation for all known cities and communities, hereinafter “places”,in the area of interest for a user of the present invention.

In a preferred embodiment, the places may be further grouped and relatedbased upon their geographic proximity to each other such as beingmembers of the same county, same state, same region, etc. The selectedgroups may be identified by minimum and maximum longitude and minimumand maximum latitude.

When determining which places are in the path of a storm, the followingsteps are performed:

1. If the places are grouped as described in the preferred embodiment,and the group's minimum latitude, minimum longitude, maximum latitudeand maximum longitude indicate that one of the places in the group arewithin the arc of the storm projection, then skip that group of places;

2. Next, for each place not eliminated in step (1) above, do thefollowing:

(a) If the place's latitude exceeds the minimum or maximum latituderequirements—skip it;

(b) If the place's longitude exceeds the minimum or maximum longituderequirements—skip it;

(c) If the place's priority level indicates that it should not appear atthis track range (based on user-defined parameter for this particulartrack)—skip it; and

(d) If the place's latitude/longitude is not within the bounding circle(see above)—skip it.

(The above elimination steps represent the preferred embodiment, butthey may be performed in any order. In addition, the user may identifyother bases for eliminating certain places from the eventual display.)

Fifth, if a particular place has not been eliminated, it is within thepath of the storm.

Sixth, by linear extrapolation, the current time, the storm's position,the storm's speed/direction, and the position of this place are used todetermine the storm's ETA for this place.

Seventh, the system displays the storm projection arc, a topographicalmap of the affected area, and iconic representations of the placesaffected (refer to FIGS. 3 and 4 for general diagrams of this step)overlaid on top of a graphical representation of the storm.

FIG. 5 illustrates a preferred embodiment of a display of projectedstorm movements, the communities within the path of a storm, and the ETAfor each community.

Finally, in the case of multiple storms, a sorting technique is used toprioritize storms. The priorities for sorting are based upon thefollowing criteria:

1. The presence of a Tornadic Vortex Signature (a.k.a. TVS). This iseither YES or NO.

2. The presence of mesocyclonic activity (a.k.a. MESO). This is eitherYES or NO.

3. The presence and estimated size of hail (size is measured in inchesand is accurate to ¼ of an inch).

4. The highest recorded DBZ (a measurement of the intensity of therainfall).

5. The estimated storm speed in mph.

These sorting criteria are in order of importance. The criteria areplugged into the following formula to determine the “weight” of thestorm. The storm with the greatest weight has the highest priority.

weight=0;

if TVS presence

weight=weight+1,000,000,000

if MESO presence

weight=weight+100,000,000

if hail size>0.00

weight=weight+hail size*10,000,000.0

weight=weight+DBZ*100

weight=weight+speed (in mph)

This formula tracks and assures that each criteria has a larger weightfactor than its successor.

It should be noted that, in addition to the storm prediction achievedthrough the novel and non-obvious use of the NEXRAD Attributes, thepresent invention improves over the prior art by merging the weather,storm, and prediction information described above with geographic andtopological information to achieve an enhanced and visually-appealingdisplay. This application allows the user to provide a graphical weatherdisplay which overlays storm information on top of actual geographicalinformation. Combining these two forms of information allows the user ofthe present invention to provide to its viewers or consumers weatherforecasting at its most advanced level.

The ease with which the user can use the present system to obtain astorm tracking prediction, is evidenced by the fact that the user needonly select the storm cell of interest, and the storm position isdisplayed automatically. Therefore, viewers of weather forecastingdisplayed through the use of the present invention will have availableprediction information specifically tailored to the viewers' own viewingarea. For instance, viewers in small towns that previously could onlyguess at what time a storm would arrive at their location may now begiven that information in a highly accurate and graphically appealingway. This improvement will detail exact and highly precise times atwhich storms or other weather phenomenon will arrive at any of severaltowns or cities in a geographical database provided with the presentinvention.

It should be understood to those skilled in the art that othermodifications and changes can be made without departing from the spiritand scope of the invention and without diminishing its attendantadvantages. It is therefore intended that such changes and modificationsbe covered by the following claims.

What is claimed:
 1. A method of using NEXRAD attributes to project apath of a storm for graphical display, said method comprising the stepsof: (a) receiving NEXRAD attributes information corresponding to a stormand storing said NEXRAD attributes information in a first database; (b)deriving a storm position in latitude and longitude from said storedNEXRAD attributes information; (c) calculating a projected storm pathusing said derived storm position and said stored NEXRAD attributesinformation; (d) displaying a graphical representation of said projectedstorm paths; (e) retrieving geographical data stored in a seconddatabase said geographical data comprising at least one area of interestincluding a plurality of populated areas; and (f) comparing saidplurality of populated areas to said projected storm path to determinewhich of said plurality of populated areas fall within said projectedstorm path.
 2. The method of claim 1 further comprising the step of: (g)displaying said plurality of populated areas falling within saidprojected storm path.
 3. The method of claim 2 further comprising thestep of: (h) indicating an estimated time of arrival of said storm onthe graphical display.
 4. The method of claim 2 wherein said stormcomprises a plurality of storms, each having an associated projectedstorm path including a storm projection arc, said method furthercomprising the steps of: (h) sorting said plurality of storms; and (i)prioritizing said plurality of storms.
 5. The method of claim 4 whereinthe step of sorting said plurality of storms comprises the steps of:comparing NEXRAD attributes information of one of said plurality ofstorms to NEXRAD attributes information of the other of said pluralityof storms; and assigning each of said plurality of storms a weight basedupon said comparing step.
 6. The method of claim 5 wherein saidprioritizing step comprises the step of displaying said plurality ofstorms by said assigned weight.
 7. A system using NEXRAD attributes toproject a path of a storm for graphical display, said system comprising:(a) a first database comprising extracted NEXRAD attributes, said NEXRADattributes comprising a first group of data and a second group of data;(b) a second database comprising stored geographical data, saidgeographical data including at least one area of interest defining aplurality of populated areas; (c) a CPU communicating with said firstdatabase to calculate a storm position in latitude and longitude fromsaid first group of data, said CPU combining said calculated stormposition with said second group of data to calculate a projected stormpath, and communicating with said second database to compare saidplurality of populated areas with said projected storm path to determinewhich of said plurality of populated areas fall within said projectedstorm path; and (d) a display device communicating with said CPU tographically display said plurality of populated areas falling withinsaid projected storm path.
 8. A method of using NEXRAD attributes toproject a storm's path on a graphical display, said method comprisingthe steps of: (a) collecting NEXRAD attributes information correspondingto a storm and storing said NEXRAD attributes information in a firstdatabase; (b) deriving a storm position from said stored NEXRADattributes information; (c) calculating a projected storm path usingsaid derived storm position and said stored NEXRAD attributesinformation; and (d) displaying a graphical representation of saidprojected storm path.
 9. A system for processing NEXRAD attributes toproject a path of a storm, said system comprising: a database comprisingNEXRAD attributes and stored geographical data, said NEXRAD attributescomprising a first group of data and a second group of data and saidgeographical data including at least one area of interest defining aplurality of populated areas; and a CPU communicating with said databaseto calculate a storm position and from said first group of data, saidCPU combining said calculated storm position with said second group ofdata to calculate a projected storm path and being instructed to comparesaid plurality of populated areas with said projected storm path todetermine which of said plurality of populated areas fall within saidprojected storm path.
 10. A method of processing NEXRAD attributes toproject a storm's path, said method comprising the steps of: (a)collecting NEXRAD attributes information corresponding to a storm andstoring said NEXRAD attributes information in a database; (b) deriving astorm position from said stored NEXRAD attributes information; and (c)calculating a projected storm path using said derived storm position andsaid stored NEXRAD attributes information.